Research Interests

Costas Stoumpos’ research expertise lies in the synthesis and material science of novel halide semiconductors with a perovskite crystal structure, AMX₃. The framework crystal structure of the perovskite is amenable to a vast synthetic parameterization and allows for control over the semiconducting properties of the materials by varying the metal ion, M²⁺, the halide anion, X^-, and the non-bonding counteraction A⁺. The research objective is the development of medium and wide band gap semiconductors (E_g = 1-3 eV) for energy applications such as photovoltaics, light-emitting devices (LEDs), lasers, nonlinear optics (NLO) and radiation detection. The project involves the full arsenal of solid-state and solvothermal synthesis methods and proceeds to the fabrication and evaluation of functional devices in the form of large single-crystals or thin-films. The character of the research is exploratory in nature, targeting new materials among the halide, chalcogenide and pnictide classes of inorganic materials, including hybrid organic-inorganic extended solids. The current directions in the laboratory revolve in the following topics:

• Low dimensional inorganic semiconductors
• Polar semiconductors and multiferroic materials
• Soft inorganic semiconductors

Short Curriculum Vitae

Costas Stoumpos was born in Athens, Greece in 1983. In 2001 he attended the Chemistry Department at the University of Patras where he obtained both his B.S. (2006) and Ph. D. (2009) degrees, the latter under the supervision of Spyros P. Perlepes working on the coordination chemistry of 3d-metals targeting the discovery of new Single-Molecule Magnets (SMMs) and Molecular Nanomagnets (MNMs). In February 2010 he joined the group of Mercouri G. Kanatzidis at the Department of Chemistry of Northwestern University, IL, USA as a postdoctoral fellow working on the synthesis of p-block halide perovskites for near-IR optical applications. On January 2012 he moved to the Materials Science Division (MSD) of Argonne National Laboratory (ANL), IL, USA, where he worked on the single-crystal growth of dense, wide-bandgap halide and chalcohalide compounds for high energy radiation detection. In 2014 he returned to Northwestern University working on the development of halide perovskites for energy related applications. Following a short coterminous appointment as Lecturer in 2017 he was promoted to the Research Assistant Professor at Northwestern University in 2017. In 2018 he was appointed at the Department of Materials Science and Technology of the University of Crete as an Associate Professor. Extended CV

Selected Recent Publications

1. C. C. Stoumpos, C. D. Malliakas, J. A. Peters, Z. Liu, M. Sebastian, J. Im, T. C. Chasapis, A. C. Wibowo, D. Y. Chung, A. J. Freeman, B. W. Wessels, M. G. Kanatzidis. "Crystal Growth of the Perovskite Semiconductor CsPbBr₃: A New Material for High-Energy Radiation Detection" Cryst. Growth Des. 2013, 13, 2722-2727
2. F. Hao, C. C. Stoumpos, Z. Liu, R. P. H. Chang, M. G. Kanatzidis. "Controllable Perovskite Crystallization at a Gas–Solid Interface for Hole Conductor-Free Solar Cells with Steady Power Conversion Efficiency over 10%" J. Am. Chem. Soc. 2014, 136, 16411-16419
3. C. C. Stoumpos, L. Frazer, D. J. Clark, Y. S. Kim, S. H. Rhim, A. J. Freeman, J. B. Ketterson, J. I. Jang, M. G. Kanatzidis. "Hybrid Germanium Iodide Perovskite Semiconductors: Active Lone Pairs, Structural Distortions, Direct and Indirect Energy Gaps, and Strong Nonlinear Optical Properties" J. Am. Chem. Soc. 2015, 137, 6804-6819
4. C. C. Stoumpos, D. H. Cao, D. J. Clark, J. Young, J. M. Rondinelli, J. I. Jang, J. T. Hupp, M. G. Kanatzidis. "Ruddlesden–Popper Hybrid Lead Iodide Perovskite 2D Homologous Semiconductors" Chem. Mater. 2016, 28, 2852-2867
5. C. C. Stoumpos, L. Mao, C. D. Malliakas, M. G. Kanatzidis. "Structure–Band Gap Relationships in Hexagonal Polytypes and Low-Dimensional Structures of Hybrid Tin Iodide Perovskites" Inorg. Chem. 2017, 56, 56-73
6. K. M. McCall, C. C. Stoumpos, S. S. Kostina, M. G. Kanatzidis, B. W. Wessels. "Strong Electron–Phonon Coupling and Self-Trapped Excitons in the Defect Halide Perovskites A₃M₂I₉ (A = Cs, Rb; M = Bi, Sb)" Chem. Mater. 2017, 29, 4129-4145
7. G. Laurita, D. H. Fabini, C. C. Stoumpos, M. G. Kanatzidis, R. Seshadri. "Chemical tuning of dynamic cation off-centering in the cubic phases of hybrid tin and lead halide perovskites" Chem. Sci. 2017, 8, 5628-5635
8. L. Mao, Y. Wu, C. C. Stoumpos, B. Traore, C. Katan, J. Even, M. R. Wasielewski, M. G. Kanatzidis. "Tunable White-Light Emission in Single-Cation-Templated Three-Layered 2D Perovskites (CH₃CH₂NH₃)₄Pb₃Br_10-xCl_x" J. Am. Chem. Soc. 2017, 139, 11956-11963
9. C. M. M. Soe, C. C. Stoumpos, M. Kepenekian, B. Traoré, H. Tsai, W. Nie, B. Wang, C. Katan, R, Seshadri, A. D. Mohite, J. Even, T. J. Marks, M. G. Kanatzidis, "New Type of 2D Perovskites with Alternating Cations in the Interlayer Space, (C(NH₂)₃)(CH₃NH₃)_nPb_nI_3n+1: Structure, Properties and Photovoltaic Performance" J. Am. Chem. Soc. 2017, 139, 16297-16309
10. A. Marronnier, G. Roma, S. Boyer-Richard, L. Pedesseau, J.-M. Jancu, Y. Bonnassieux, C. Katan, C. C. Stoumpos, M. G. Kanatzidis, J. Even. "Anharmonicity and Disorder in the Black Phases of Cesium Lead Iodide used for Stable Inorganic Perovskite Solar Cells" ACS Nano 2018, 12, 3477-3486
11. L. Mao, W. Ke, L. Pedesseau, Y. Wu, C. Katan, J. Even, M. R. Wasielewski, C. C. Stoumpos, M. G. Kanatzidis. "Hybrid Dion-Jacobson 2D Lead Iodide Perovskites" J. Am. Chem. Soc. 2018, 140, 3775-3783
12. P. Guo, W. Huang, C. C. Stoumpos, L. Mao, J. Gong, L. Zeng, B. T. Diroll, Y. Xia, X. Ma, D. J. Gosztola, T. Xu, J. B. Ketterson, M. J. Bedzyk, A. Facchetti, T. J. Marks, M. G. Kanatzidis, R. D. Schaller. "Hyperbolic Dispersion Arising from Anisotropic Excitons in Two-Dimensional Perovskites" Phys. Rev. Lett. 2018, 121, 127401